Topicmfd91f394758527e1_1528449000663_0Topic

CalculatingcalculatingCalculating the areaareaarea of the rectanglerectanglerectangle and the squaresquaresquare

Levelmfd91f394758527e1_1528449084556_0Level

Second

Core curriculummfd91f394758527e1_1528449076687_0Core curriculum

XI. Calculation in geometry. The student:

2) calculates the areaareaarea of: the triangle, the squaresquaresquare, the rectanglerectanglerectangle, the rhombus, the parallelogram and the trapezium, presented in the figure and in practical situations, including data which require the conversion of units and in situations in which the dimensions are not typical, e.g. the areaareaarea of a triangle with side 1 km and the altitude of 1 mm;

3) uses the units of the areaareaarea: mmIndeks górny 2², cmIndeks górny 2², dmIndeks górny 2², mIndeks górny 2², kmIndeks górny 2², are, hectare (without the conversion of the units in calculation);

Timingmfd91f394758527e1_1528449068082_0Timing

45 minutes

General objectivemfd91f394758527e1_1528449523725_0General objective

Matching the mathematical model to a simple situation and using it in various contexts.

Specific objectivesmfd91f394758527e1_1528449552113_0Specific objectives

1. CalculatingcalculatingCalculating the areaareaarea of the rectanglerectanglerectangle and the squaresquaresquare.

2. Using the formula of the areaareaarea of the rectanglerectanglerectangle in practice.

3. Communicating in English; developing mathematical and basic scientific; technical and digital competences; developing learning skills.

Learning outcomesmfd91f394758527e1_1528450430307_0Learning outcomes

The student:

- Does the preliminary activities to make solving the task easier including the supporting drawing, the records of the information and the data of the tasks.

- Calculates the areaareaarea of the rectanglerectanglerectangle.

Methodsmfd91f394758527e1_1528449534267_0Methods

1. Brain storming.

2. Situational analysis.

Forms of workmfd91f394758527e1_1528449514617_0Forms of work

1. Individual work.

2. Class work.

Lesson stages

Introductionmfd91f394758527e1_1528450127855_0Introduction

Teacher introduces the topic of the lesson. The students are going to solve the tasks improving their ability of calculatingcalculatingcalculating the areaareaarea of the rectanglerectanglerectangle.

The students revise the method of calculatingcalculatingcalculating the areaareaarea of the rectanglerectanglerectangle and the squaresquaresquare.

- The areaareaarea of the rectanglerectanglerectangle with the sides of a and b is expressed by the formula $P=a·b$.

- The areaareaarea of the squaresquaresquare with the side of a is expressed by the formula: $P=a·a$ or $P=a^2$.

Proceduremfd91f394758527e1_1528446435040_0Procedure

The student work using the brainstorming method. They give the examples of calculatingcalculatingcalculating the areaareaarea of the rectanglerectanglerectangle in their everyday life. They specify the units to express the following:

a. the areaareaarea of the piece of paper, b. the areaareaarea of the building plot, c. the areaareaarea of the lake, d. the areaareaarea of the country.

[Slideshow]

The students work individually using their computers. They are going to discover the examples of calculatingcalculatingcalculating the areaareaarea in a practical context by using their abilities.

Task 1
The floor in the flat of the Browns is in a shape of the squaresquaresquare with the dimensions of 3 m by 4 m. How much money will the Browns pay for the laying the terracotta tiles if one squaresquaresquare metre of the tiles costs 35 PLN?

Task 2
Calculate the areaareaarea of a squaresquaresquare whose perimeter is 36 cm.

Task 3
The mattress in a bed has the dimensions of 150 cm by 200 cm. The bed coverlet is made of ten rectangular pieces of fabric with dimensions of 50 cm x 1 m. What are the dimensions of the coverlet if it covers the whole surface of the bed? Calculate the areaareaarea of the bed coverlet.

Task 4
The rectangular label has the dimensions of 9 cm by 93 mm. What is the areaareaarea of the label?

Conclusion:
If you want to calculate the area of the rectangle the length of its sides should be express in the same units.mfd91f394758527e1_1527752263647_0If you want to calculate the area of the rectangle the length of its sides should be express in the same units.

An extra task:
We use 20 matches to make the rectanglerectanglerectangle. Using all the matches every time we are able to make 5 different rectangles. Write their dimensions taking the length of one match as a unit. Which of the rectangles has the largest areaareaarea? Which of them has the largest perimeter?

Lesson summarymfd91f394758527e1_1528450119332_0Lesson summary

The students do the summarising tasks .

Then they sum up the classes, drawing conclusions to memorise:

If you want to calculate the areaareaarea of the rectangle the length of its sides should be express in the same units.

Selected words and expressions used in the lesson plan

areaareaarea,

calculatingcalculatingcalculating,

dimensiondimensiondimension,

largest arealargest arealargest area,

quadranglequadranglequadrangle,

rectanglerectanglerectangle,

smallest areasmallest areasmallest area,

squaresquaresquare,

surface areasurface areasurface area